Rainbow Monkeys comes from Codename: Kids Next Door, the Cartoon Network series that ran in the 2000s, where the toys were a running obsession for Numbuh 3. Within the show the brand had its own songs, dolls and episodes built around collecting them. Clips of the jingle later spread on soundboards and in fan edits because the tune is instantly recognisable to viewers who grew up with the series. Its mix of earnest lyrics and bright colours keeps it in use for nostalgic and ironic posts.